Series of a USAF RF-4C reconnaissance aircraft being shot down by an SA-2 on Aug. 12, 1967 near Hanoi, North Vietnam. Capts. Edwin Atterberry and Thomas Parrott were captured after ejecting. Atterberry died in the hands of the North Vietnamese after an escape attempt and Parrott was released at the end of the war.(U.S. Air Force photo)

Series of a USAF RF-4C reconnaissance aircraft being shot down by an SA-2 on Aug. 12, 1967 near Hanoi, North Vietnam. Capts. Edwin Atterberry and Thomas Parrott were captured after ejecting. Atterberry died in the hands of the North Vietnamese after an escape attempt and Parrott was released at the end of the war.(U.S. Air Force photo)

Series of a USAF RF-4C reconnaissance aircraft being shot down by an SA-2 on Aug. 12, 1967 near Hanoi, North Vietnam. Capts. Edwin Atterberry and Thomas Parrott were captured after ejecting. Atterberry died in the hands of the North Vietnamese after an escape attempt and Parrott was released at the end of the war. (U.S. Air Force photo)

Series of a USAF RF-4C reconnaissance aircraft being shot down by an SA-2 on Aug. 12, 1967 near Hanoi, North Vietnam. Capts. Edwin Atterberry and Thomas Parrott were captured after ejecting. Atterberry died in the hands of the North Vietnamese after an escape attempt and Parrott was released at the end of the war.(U.S. Air Force photo)

F-105 trailing smoke just after interception by an SA-2. The SA-2 did not actually hit an aircraft—the fuse automatically went off when it neared the target, throwing deadly fragments over a wide area. (U.S. Air Force photo)

Taken over North Vietnam in January 1967, this photograph illustrates the difficulty of visually spotting a SAM site. Wild Weasels used specialized electronic equipment to find the SAM sites. Red arrows in closeup point to the six SA-2 launchers in revetments. (U.S. Air Force photo)

Distinctive star-shaped layout is evident in this SA-2 site in Cuba in November 1962. After the first Wild Weasel successes, the North Vietnamese began laying out the sites irregularly to make them harder to spot. (U.S. Air Force photo)

Developed in the mid-1950s, the V-750 Dvina was the first effective Soviet surface-to-air missile. The Soviets used it to shoot down Gary Powers' U-2 over the USSR in 1960 and Maj. Rudolph Anderson's U-2 over Cuba in 1962. The missile was better known by the NATO designation SA-2 Guideline. The Soviets began exporting it to many countries worldwide in 1960, with many remaining in use into the 21st century.

North Vietnam began receiving SA-2s shortly after the start of Operation Rolling Thunder in the spring of 1965. With Soviet help, they built several well-camouflaged sites, regularly moving SA-2s and their equipment among them. The North Vietnamese also ringed SA-2 sites with anti-aircraft artillery (AAA), making them even more dangerous to attack.

SA-2 Site
The SA-2 did not operate alone, but as part of a complete system. A typical SA-2 site in North Vietnam had six missiles on launchers, control and support vans, a Spoon Rest acquisition radar, and a Fan Song guidance radar.

The Spoon Rest radar detected incoming aircraft at long range (as far as 70 miles), providing location data to the system computer.

The Fan Song guidance radar performed two functions: target acquisition and missile guidance. It acquired as many as four targets before firing. After launch, it guided up to three SA-2s against one target. (The North Vietnamese sometimes placed the radars away from the missiles to make the site harder to destroy.)

The SA-2 missile had a solid fuel booster rocket that launched and accelerated it, then dropped off after about six seconds. While in boost stage, the missile did not guide. During the second stage, the SA-2 guided, and a liquid-fuel rocket propelled it to the target.

How Radar Works
Radar (Radio Detection And Ranging) can be likened to shouting in a valley and hearing an echo in return. A radar emitter sends out radio waves, which hit an object and reflect back to a radar receiver. Much information can be gained by calculating the time and angle of the reflected radio waves.

Basic radar can simply indicate the presence of an object from several miles away, while more advanced radars can provide the speed, altitude and heading of an aircraft. Radar information can be used in many ways, including providing early warning of an attack, directing defensive fighters, aiming anti-aircraft artillery fire and guiding missiles (including SAMs).

SA-2 Guideline (V-750VK Dvina) Surface-to-Air Missile and Launcher
The reusable SA-2 launcher rotated 360 degrees and typically raised the missile between 30 and 60 degrees for launch. Removable wheels (not displayed) allowed the launcher to be moved quickly. In fact, North Vietnamese SAM crews could pack up and move a site in about four hours.

One vital capability of the Wild Weasels was being able to identify and immediately strike an active site. Before the Wild Weasels, the enemy often moved out of a site by the time a strike force was put together to hit it.

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